Vacuum inducing construction



Nov. 18, 1930.

A. DODGE VACUUM INDUCING CONSTRUCTION Filed Sept 29. 192'? INVENTOR Y ,Doige:

ATTORNEYS Patented Nov. 18, 1930 ADIEL Y. DODGE, OF soU'rH BEND, INDIANA vAoU M rnno e rne oons'rn-ucrron Application filed September 29, 1927. Serial No. 222,705.

My invention relates to a a construction. 1

One of the objects of my invention is to provide improved means whereby the de- 5 sired vacuum maybe obtained from a con nection with the intake conduit of an internal combustion engine, regardless of the posi tion of the throttle.

The static pressure inintake manifold va- 10 ries with the position of the throttle, the vacuunr decreasing as the throttle is opened.

To compensate for theadecrease in substatic pressure I provide an induction device controlled by the-velocity'ot flow of gas in the 1-5 manifold which modifies the effect of the static pressureian'd gives the desired vacuum regardless of the throttle position.

In the drawings inwhich several forms of'niy invention are shown Figure 1 is a 'sideelevation showing my improved inductiondevice installed in the intake manifold oi anfinternalcombustion engine; I 7

Fig. 2 is a similar view showing a different 25 installation for the induction device F ig.-3 is an enlarged View of the induction device showing details of construction;

Fig.4 is a section on the line 4-4015 Fig. 3; Fig. 5 isa longitudinal section view of a somewhat different form of induction device;and I Fig. 6 is a'longitudinal sectional view of still another form of induction device.

Referring to the drawings in detail and first 33 to Figs. 1 to 4;, inclusive, the construction shown therein comprises the intake manifold 1 of'an internal combustion engine having a trunk passage 2 leading from the carburetor, and two branch passages 3 and dleading from the trunk the induction device 5 being located inthe trunk passage. Thi's inducti'on' device may be connected by a-suitable conduit 6 with any device in which it is desirable to maintain a vacuum: such the well known We uum tank for use in supplying fuel to the carburetor on a suction operated device 6 for operating a windshield cleaner 6 In these suction operated devices it is desirable thatthe suction should be maintained subvacuum inducing passage 2 to the engine cylinders,-

stantially constant regardless of the position of the throttle and this desirable condition will not beobtained if dependence "is placed solely on the static pressure in the intake manifold asthe suction due to this static pressure decreases materially when the throttle is open wide. Itlis common knowledge that suction operated windshield wipers fre quently cease to operate when the throttle is opened wide, due'to the decrease in suction. In order to compensate for this decreasei-n the static pressure I provide a suction inducing device comprising a tubular n'iemberhavmg an enlarged head portion 8 located in the line of flow of the gas, indicated by arrows A, and a. reduced shankportion 9 having a longitudinal passage 10 in communication with the suction conduit 6 and leading to a position adjacent the enlarged head, and having a; transverse passage-way 11 which places saidlongitudinal passageway in communication with the'intake conduit 3, said transverse passageway opening into the intake conduit at a place adjacent the juncture'of the shank 9' and head 8. This transverse passage in Fig. 1 extends at right angles to the line of fiowof gas in the intake manifold, so that the kinetic energy of. the gas causes a reduction of pressure as it flo s around theshank oi the tubular member, modifyingthe'effect of the static pressure 011 the suction conduit. Thus the effect of the variation of static pressure in the manifold on thesuction conduit is compensated for by the eiiect due toithe variation of velocity of flow or the gas in the manifold.

In assembly, the head 8 of the suction in-. ducing device :is inserted through a threaded opening in the manifold l, and the threaded portion 12 of the suction inducing device isscrewed into this threaded opening until a gas-tight fit is secured. The upper end of the suction inducing device is provided with a conical seat 13 for engagement with a flarns P I'ti'on 1410f the suction cond it which is snugly held against this conical seat by means of a clamping nut 15 having a threadt ed engagement with the suction inducing device i In Fig.2 the suction inducing device is ings 19, and the upper end being shown as installed at thejuncture of the two branch passages with the head facing the from the carburetor trunk passage 2 leadin and throttle valve, so t iat the head faces the direction of flow from this trunk passage, indicated by arrows B. In this construction the flow of. gas adjacent and around the head creates a suction back of the head due to the velocity of the gas which modifies the effect of the static pressure in the manifold.

The construction shown in Fig. 5 is similar to that just described except that the taper 0f the head 8 is concave instead of convex, which may be desirable for certain designs of intake manifold.

In Fig. 6 is shown a construction in which the suction device is made up largely of sheet material or tubular material; In this form a tubular member 16 of sheet material is fitted snugly into a suitably threaded bushing '17, the lower end being shaped and formed to provide the head portion 18 with lateral openiiared outwardly at'QO for engagement with a conical seat portion 21 on the bushing 17. The connection with the suction conduit is effected by means of a clamping nut and spacing washer 23, the suction conduit 6 having a portion 14:- flared out to engage a conical seat portion 2d on the clamping nut 22, and the spacing washer 23 being located between the flared "portion 20 of the tubular member and the flared portion 14; of the suction conduit.

1 The operation has been outlined in co iection with the descriptionof the construction. An increasein the opening of the throttle valve has two compensating effects on the suction in the suction conduit. Opening the throttleincreases the'static pressure in the manifold and it also increases the velocity i of flow of the gas in the intake manifold The increaseof static pressure tends to reduce the suction in the suction conduit but the increase of velocity of gas flow tends to increase the suction 1n the suction conduit. By properly designing the suctioninducing device the resultant suction in the suction conduit may be maintained at the desired amount 7 regardless of the throttle position.

I claim:

1 A suction inducing device having provisions for communication with a suction conduit and an intake conduit of an internal combustion engine comprising atubular member having an enlarged head portion and a reduced shank portion, said shank portion having a longitudinal passage inconimuiiication wthsaid suction conduit and leading to a position adjacent said enlarged head and having a transverse passage-way which places said longitudinal passage-way in communi cation with said intake conduit, said transverse passage-wayopening into said intake conduit at a place adjacent the junction of the shank and head.

take conduit at a place adjacent the junction of the shank and head, said head having a tapering point facing the direction of flow in said intake conduit.

'3. A suction inducing device having provisions for communication with a suction conduit and an intake manifold of an internal combustion engine comprising a tubular member having an enlarged head portion and a reduced shank portion, said shank portionhaving a longitudinal passage in communication with said suction conduitand leading to a position adjacent said enlarged head and having a transverse passage-way which places said longitudinal passage-way in communication with said intake manifold, said transverse passage-way opening into said intake manifold at a place adjacent the junction of the shank and head, said intake manifold having a passage leading from the carburetor and two branch passages leading in opposite directions from said first passage, the axis-of said shank extending longitudinally with respect to the axis of said first passage-way.

4. A suction inducing device in communication with a suction conduit and intake conduit of an internal combustion engine com prising a tubular member having an enlarged head portion and a reduced shank portion, said shank portion having a longitudinal passage in communication with said suction conduit and leading to a position adjacent said enlarged head and having a transverse passage-way which places said longitudinal passage-way in communication with said intake conduit, said transverse passage-way opening into said intake conduit at a place adj acent the junction of the shank and head, said intake conduit having a screw threaded opening therein through which the head of said suction inducing device may be inserted into said intake conduit, and said suction inducing device having a screw threaded por tion threaded into said opening.

In witness where-of, Ihave hereunto subscribed my name.

ADIEL Y. DODGE. 

